Process of removing surface finish



Feb. 3, 1925.

Filed Sept. 5, 1924 ISO Patented Feb. 3, 1925.

' UNITED STATES PATENT OFFICE.

DAVID P. CLEVELAND, OF OAKLAND, CALIFORNIA, ASSIGNOR, TO UNIVERSAL PAINT BEMOVER AND MOTOR CLEANING COMPANY, OF DALLAS, TEXAS, A COMMON-LAW COMPANY.

PROCESS OF REMOVING SURFACE FINISH.

Application filed September 5, 1924. Serial No. 736,042.

To all whom it may concern:

Be it known that 1, DAVID P. CLEVELAND, a citizen of the United States of America, residing at Oakland, in the county of Alameda and State of California, have invented certain new and useful Improvements in Processes of Removing Surface Finish, of which the following is a specification.

This invention relates to new and useful improvementsin processes of removing surface finish.

The invention has particularly to do with the direction upon a surface'of a hot fluid containing caustic alkali or equivalent ingredients.

The invention has particularly to do with the direction upon a surface of a hot fluid containing caustic alkali or equivalent inredients. Heretofore such fluids have been blown or ejected ontothe surface. under pressure, such as steam and air.

In my Patent No. 1,355,074, Oct. 5th, 1920, the process described involves the applying of a caustic alkali solution by means of a pressure, such as steam. The solution is atomized or ejected by means of a pressure. I have found that under certain weather conditions a cloud or mist is pres-- cut at the work, in such a form as to obscure the work. I have also discovered, by experiment and research, that the alkaline liquor may be applied at a temperature be low the boilingpoint of water and free from steam or air pressure, with very satisfactory results; also at a less cost than is possible with my aforesaid patented process.

The principal object of the invention is to deliver the alkaline solutionto the surface in a simple and inexpensive manner and to overcome certain objections present lIl'OlllOI processes. \Vhere the solution is put on the surface by steam or where steam is sprayed onto the surface at the same time, a cloud or ban of vapor obscures the work from the view of the workman particularly during cold weather. \Vhere air is used it must be compressed and heated and conveyed to the work while hot. A further object of the invention is to flow a hot alkaline solution onto the surface, whereby the finish is softened or disintegrated, so that'it may be later removed by means of a brush or other means.

Another object is to apply a hot caustic alkaline solution at a substantially constant temperature and a substantially constant fixed strength.

1n carrying out. the invention I elevate a tank containing the alkaline solution, heat said solution and utilize gravity in flowing it onto the surface for the finish to be removed. The solution upon reaching. the

surface may have a temperature ranging from 1.50 degrees Fahrenheit to 200 degrees, Fahrenheit. A fter the alkaline solution has been delivered to the surface, a jet of steam may be sprayed upon the same to clean it, or hot water or air may be employed; the process being finished up with a stream of cold or unheated water. The use of steam may be entirely eliminated by flowing the hot alkaline solution onto the surface to .soften or disintegrate the finish, and then designed to carry out the invention.

Fig. 2 is a cross section taken on the line 2-2 of Fig. 1, and

Fig. 3 is/a front elevation of a rack upon which vehicles may be driven for treatment.

In the drawings the numeral 10 designates' a suitable tank havinga filling pipe 11 in its top, said pipe including a cut-off valve 11'. This tank must be placed at a suitable elevation above the work to obtain a gravity flow. I have shown the tank mounted in a. bracket 12 supported on a column 13, but it may be supported in any suitable manner, as on an upper fi'oor in the building where the work is being done.

The alkaline liquid placed in the tank 'nmst be heated and I do not wish to he limitedto the means, manner or method of so heating, or to the degree of temperature to which it is heated. l have found it practical and satisfactory to mount a coil 14 in the tank with its upper end [no truding through the top of said tank and its lower end projecting through the side of the tank near the bottom of the latter. Steam is supplied to the coil by a pipe 15 which is connected with an elbow 15 so that the coil may be disconnected and the tank removed when desired. lvlostany form of receptacle, suitable for the purpose may be used and any desirable heating medium may be employed for heating the liquid in the receptacle.

The lower end of the coil extends through the side of the tank near the bottom. A valve 14 is connected in the extension of the coil outside of the tank. A hose i6 is connected with the coil and has a nozzle 17 on its lower end by which steam or hot water may be directed upon the work, but

the;' nozzle may be omitted. A discharge pipe 18 leads from the tank under the coil extension and includes a controlling valve 18.- A hose has its upper end connected with the pipe 1,8 and is provided with a noz- Z1020 at its lower end. water or other fluid a pipe 21 is supported by the column 13 and includes a controlling valve 21'. A hose 22 leads from the pipe and has a nozzle 23 on its end.

For the purpose of illustration I have shown a rack 24 on which an automobile may be supported, but it is to be understood that the invention is neither to be l mited to the apparatus shown or the removing of finish coating from any particular object.

The essential feature of the. invention is the application of a hot finish removii-g liquid by a gravity flow and the elim nation of steam or other fluid under pressure as an agent in applying said liquid. In order that the best results may be had it is nee- I work.

In removing finish coatings the hot alkaline solution is admitted tot-he hose 19 by opening the valve 18 and permitting said liquid to flow from the nozzle 20 onto the surface. tegrated and will flow in a solvent state from the article being treated. The surface may be washed with steam or hot water from the coil by opening the valve 1 1 and directing the nozzle 17 toward the work. Water or air may be obtained from the hose 22 and nozzle 23.

If desired the heated solution may be ap lied to the surface, sulliciently hot to soften or disintegrate the finish. which may be removed by means of a stiff brush, and the surface finally washed off.

This method is simple and inexpensive as it obviates thej necessity of using pressure to at the finish removing liquid'on the sur ace and does away with the use of steam For supplying air,

The finish coating will be disin-- if desired as the coil may be connected with a return to the boiler. The finish removing liquid is flowed onto the surface by gravity and is never impelled or sprayed by steam or air pressure. While steam may be used by directing it on the' work to remove the softened or disintegrated finish, said steam is applied separately and not as'a spray or conductor for the removing fluid. Also the steam may be supplied from any source and need not come from the coil 14. which would be omitted if the tank was otherwise heated. The solution is maintained at substantially a constant ten'iperature, but is subject to variation. The liquid is also kept at a substantially fixed strength for each operation.

This application is a cont nuation, in part of my application Serial No. 544.364. filed March 16, 1922. I

\Vhatl claim, is:

1. A process of removing finish coating consisting in heating an alkaline solution to a temperature above 1.30 degrees Fahrenheit and below the boiling point of water, and then [lowing said-solution without artificial pressure onto the surface to be treated in a solid continuous stream of restricted cross area.

2. A process of removing finish coating, which consists in heating an alkaline solu tion in an elevated tank to a temperature above 150 degrees Fahrenheit and below the boiling point of water, then flowing said solution in a solid continuous stream of restricted cross afea by gravity onto the surface being treated, said solution being applied free from steamer artificial pres sure, and then utilizing the heating agent for cleansing the surface treated. Y

3. A process of removing finish coating. which comprises-the steps oi. flowing inn solid continuous stream of restricted cross area by gravity upon the surface being treated, a hot alkaline solution maintained at a temperature less than the boiling point of water and at a substantially constant strength during the entire flowing operation, then removing the disintegrated finish by the application of steam. and then washing the surface with water.

4. A process of removing finish coating from an article, which consists in heatin an alkaline solution in an elevated tank t3 a temperature above 150 degrees Fahrenheit and below the boiling point of water, and then. flowing said solution in a solid continuous stream of restricted cross area by gravity onto the surface being treated, said solution being applied free from steam or artificial. pressure.

t In testimony whereof I afiix my signaure.

DAVID P. CLEVELAND. 

